Aileron control for model airplanes



July 9; 1968 P. w. DARIN 3.391. 3

AILERON CONTROL FOR MODEL AIRPLANES Filed Dec. 21, 1965 /3a INVENTOR.

. EA. 7 C

om/r x States This invention relates to model airplanes and inparticular to improvements in the aileron control linkage for a remotelycontrolled toy or model airplane.

In one type of model airplane which flies under its own power, a radiocontrolled motor is operatively connected with the ailerons to actuatethe same and guide the airplane in response to predetermined signalsfrom a ground based transmitting station. In such operation, one aileronis raised and the other is lowered simultaneously to bank and steer theairplane while in flight. Frequently after assembly of the lightweightand fragile model airplane, the ailerons will not be in properadjustment for flight conditions, or the aileron control motor willrespond to the signal from the ground to actuate one or both of theailerons either excessively or inadequately, rendering control of theairplane diflicult and often necessitating adjustments that aredifficult to make in the field.

An important object of the present invention is to provide a simplifiedand economical aileron control linkage which is positive and etficientin operation, which is readily responsive to actuation by a small radiocontrolled motor carried by the airplane, and which is readilyadjustable in the field to assure pro-per effectiveness of the aileroninfluence without recourse to special tools or equipment.

Other objects of this invention will appear in the following descriptionand appended claims, reference being had to the accompanying drawingsforming a part of this specification wherein like reference charactersdesignate corresponding parts in the several views.

FIGURE 1 is a fragmentary plan view of the central portion of a modelairplane, showing the aileron control linkage and a portion of the frontwing.

FIGURE 2 is a transverse sectional view taken in the direction of thearrows substantially along the line 2-2 of FIGURE 1.

FIGURE 3 is an'enlargcd sectional view through the nut member of thelinkage adjustment, taken in the direction of the arrows substantiallyalong the line 33 of FIGURE 2.

FIGURE 4 is an enlarged sectional View through the aileron, showing itsattachment with the control linkage.

FIGURE 5 is a view similar to FIGURE 3, showing a modification.

It is to be understood that the invention is not limited in itsapplication to the details of construction and arrangement of partsillustrated in the accompanying drawings, since the invention is capableof other embodiments and of being practiced or carried out in variousways. Also it is to be understood that the phraseology or terminologyemployed herein is for the purpose of description and not of limitation.

Referring to the drawings, a particular embodiment of the presentinvention is illustrated by way of example with a model airplaneconventionally fabricated from lightweight frame materials such as balsaand thin plywood sheets covered by a suitable taut fabric to comprise abody 10, which includes the customary fuselage and front wing structure11. An operable air of ailerons 12 are arranged along the trailing edgeof the wing 11 symmetrically with respect to the longitudinal centerlineof the airplane and are pivotally secured thereto by suitatent O iceable means including part of the aileron operating linkage.

In the present instance, each aileron is associated with a wire rodmember 13 of steel or suitable rigid material having an axial extension1311 which terminates in an integral transverse and generally rearwardprojection 13b embedded and secured with a solid portion of the aileron12. A lateral portion of the extension 13a is recessed along its lengthinto the leading edge of the aileron, FIG- URE 4, to lie flushtherewith, the extension 13a continuing along the trailing edge of thewing 11 beyond the aileron 12 and extending pivotally through a tubularbushing 14 suitably laced on the wing 11, as for example by nylon thread15. Medially of the bushing 15, the extension 13a terminates in anupright screw threaded extension on which one end of a connecting linkmeans 16 is secured in preselected vertically adjusted position. Theouter end of each aileron 12 is also pivotally secured to the wing 11for pivoting about the longitudinal axis of the extension 13a. The outeraileron pivot may comprise a pivot rod similar to the extension 13a,secured at one end to the aileron 12 and extending pivotally through atubular bushing laced to the wing 11 in the manner of the bushing 14.

The link means 16 comprises a rigid steel connecting wire link 16asecured at its opposite ends to a pair of spring clips 17, as bysoldering to prevent loosening during flight. The two clips 17 connectedwith each link 16a may be identical, each comprising a tubular socket17a within which the associated end of link 16a is soldered, and a pairof spring arms 17b extending integrally from the socket 17a. One of thespring arms 17b is welded to a pin which extends towards the otherspring arm 17b and is removably confined within a hole 17d there- Theclip 17 at the rear end of each link 16a is pivotally and removablysecured to a tab 18a integral with a nut member 13 screwed on uprightextension 130 in adjusted position. The nut 18 is preferably a moldedplastic member, such as nylon and may be self threading by being screwedon to extension 13c to eflect a cornparatively tight frictionalengagement therewith. Each tab 18a is formed with a bore through whichthe pin 170 of the associated clip 17 freely extends. Spring tensioncauses the clip arms 17b to grip the tab 18a therebetween and preventtheir accidental disassembly from the tab 18a. However moderate fingerpressure will suffice to spread the spring arms 17 apart to enableseparation of pin 170 from the tab 180, whereby the nut 18 may then bereadily screwed to adjusted position along the length of the threadedextension 130.

Each of the clips 17 at the forward ends of the links 16a is pivotallysecured at 1911 to one of the swinging ends of a double arm crank 19pivotally mounted at 1% on the housing 20 for a radio controlled aileronactuating motor. The housing 26 may be of lightweight metal or rigidplastic and is suitably secured to the body 10 by a plurality of screws21. It contains a motor having an actuating lever 22 extending through aslot 23 in housing 20. The motor is responsive to preselected signals ata predetermined radio frequency or wave length to swing the rod 22forward or rearward along slot 23 and may be conventional. The lever 22is pivotally connected at one end 24a of a rigid wire link 24-, thelatters other end 24b being pivotally connected with a boss on one armof the crank 19.

In operation, while the airplane is in flight, the operator on theground may signal the motor within housing 20 to swing rod 22 forward orrearward, as desired, thereby to swing crank 19 counterclockwise orclockwise in FIG- URE l and, by virtue of linkage 16, 17, 18 to swingone aileron upwardly and the other downwardly about the pivot axis ofthe coaxial rod extensions 13a. By detaching either of the clips 17 fromthe nut tab 180, the corresponding nut 18 can be screwed up or downalong the length of the upright extension 130 to predetermine the extentof aileron movement in response to a given pivotal movement of thedouble arm crank 19. It is apparent that the higher the position ofadjustment of the nut 18, the less will be the pivotal movement of theassociated aileron with respect to the pivotal movement of the crank 19.

The structure described has the advantage that by reason of the tightscrew threaded engagement between nut 18 and extension 130 the nut 18cannot turn after the link 16a is connected to tag 18a and crank 19.Thus accidental movement of the nut 18 along the length of extension 13cis prevented. However, detachment of one of the spring clips 17, fromeither crank 19 or tab 18a, and preferably from the latter, is necessaryto efiect the adjustment of nut 18.

In FIGURE 5, instead of nut 18, a member 18 having a bore oversize withrespect to threaded extension 13c is freely slidable along the latter.In this modification, the member 18 is tightly clamped in adjustedposition between a pair of lock nuts 24 screwed on extension 13c. In allother respects, the aileron control structure is the same as describedabove.

I claim:

1. In a model airplane, a body including a wing, an aileron pivotallyconnected to an edge of said wing, means comprising in part the pivotalconnection between said wing and aileron comprising a rod member havingan axial extension coaxial with the pivot axis of said aileron and fixedto said aileron to pivot therewith and also having an integral uprightswinging extension transverse to said pivot axis, means pivotallysecuring said axial extension to said wing, link means extendingtransversely from said upright extension and also transversely to saidpivot axis, and means for adjustably securing one end of said link meansto said upright swinging extension at preselected locations along thelength of the latter for swinging said upright extension and integralaxial extension and connected aileron about said pivot axis uponactuation of said link means.

2. In the combination according to claim 1, one end portion of saidaxial extension being secured to said aileron coaxially with the latterspivot axis and the opposite end portion of said axial extension beingpivotally secured to said wing.

3. In the combination according to claim 2, said means for adjustablysecuring one end of said link means to said upright swinging extensioncomprising screw threaded means.

4. In the combination according to claim 2, said swinging extensionhaving a screw threaded portion extending along its length, and saidmeans for adjustably securing one end of said link means to saidswinging extension comprising screw threaded means.

5. In the combination according to claim 4, said screw threaded meanscomprising a plastic nut member in frictional and screw threadedengagement with said screw threaded portion of said swinging extension,said nut member having a tab, and said tab and one end of said linkmeans having cooperating portions detachably connected, whereby said nutmember is adjustable axially of said screw threaded portion upondetachment of said nut member from said link means.

6. In the combination according to claim 2 wherein the elementsincluding said aileron, means comprising in part the pivotal connectionbetween said wing and aileron, means pivotally securing said axialextension to said wing, link means, and means for adjustably securingsaid link means and swinging extension each comprise one of a pair ofsuch elements spaced by the longitudinal center plane of said airplane,the pair of rod members being mirror images of each other and eachhaving an integral transverse projection at said one end thereofembedded into the body of the associated aileron for rigid attachmentthereto, and bell crank means pivotally mounted on said body at alocation between the pair of link means and having a pair of crank armsextending laterally from its pivot axis toward and connected to the endsof said pair of link means respectively opposite said one end thereoffor swinging said pair of ailerons in unison and in opposite directionswith respect to each other upon pivoting of said bell crank means.

7. In the combination according to claim 6, said means for adjustablysecuring one end of each link means to its associated upright swingingextension comprising screw threaded means.

8. In the combination according to claim 6, each swinging extensionhaving a screw threaded portion extending along its length, and saidmeans for adjustably securing one end of each link means to saidswinging extension comprising a separate nut member in screw threadedengagement with each screw threaded portion, each nut member having atab, each tab and the one end of the associated link means havingcooperating detachably interconnected portions, whereby said nut memberis adjustable axially of said screw threaded portion upon detachment ofsaid nut member from said link means.

9. In the combination according to claim 6, each swinging extensionhaving a screw threaded portion extending along its length, and saidmeans for adjustably securing one end of each link means to saidswinging extension comprising a separate nut member in screw threadedengagement with each screw threaded portion, each link means comprisingtwo link portions detachably interconnected between its ends, wherebysaid nut member is adjustable axially of said screw threaded portionupon detachment of said two link portions.

10. In the combination according to claim 4, said screw threaded meanscomprising a nut member at said one end of said link means, actuatingmeans connected to the other end of said link means, said link meanscomprising two link portions detachably interconnected at a locationbetween said nut member and said other end, whereby said nut member isadjustable axially of said screw threaded portion upon detachment ofsaid two link portions from each other.

References Cited UNITED STATES PATENTS 2,478,033 8/1949 Weick 244902,858,386 10/1958 Bonner 4676 3,110,127 11/1963 Bencsch 4677 LOUIS G.MANCENE, Primary Examiner.

R. F. CUTTING, Assistant Examiner.

1. IN A MODEL AIRPLANE, A BODY INCLUDING A WING, AN AILERON PIVOTALLYCONNECTED TO AN EDGE OF SAID WING, MEANS COMPRISING IN PART THE PIVOTALCONNECTION BETWEEN SAID WING AND AILERON COMPRISING A ROD MEMBER HAVINGAN AXIAL EXTENSION COAXIAL WITH THE PIVOT AXIS OF SAID AILERON AND FIXEDTO SAID AILERON TO PIVOT THEREWITH AND ALSO HAVING AN INTEGRAL UPRIGHTSWINGING EXTENSION TRANSVERSE TO SAID PIVOT AXIS, MEANS PIVOTALLYSECURING SAID AXIAL EXTENSION TO SAID WING, LINK MEANS EXTENDINGTRANSVERSELY FROM SAID UPRIGHT EXTENSION AND ALSO TRANSVERSELY TO SAIDPIVOT AXIS, AND MEANS FOR ADJUSTABLY SECURING ONE END OF SAID LINK MEANSTO SAID UPRIGHT SWINGING EXTENSION AT PRESELECTED LOCATIONS ALONG THELENGTH OF THE LATTER FOR SWINGING SAID UPRIGHT EXTENSION AND INTEGRALAXIAL EXTENSION AND CONNECTED AILERON ABOUT SAID PIVOT AXIS UPONACTUATION OF SAID LINK MEANS.